Can the microphone be used to make a phone call?

Smartphones' headphone jacks were designed for headphones, it's just like the name sounds. So, when you plug in anything other than a headphone, it sees it as sees as a microphone and a headphone at the same time.

In other words, the built-in speaker of your smartphone stops working, So, while you can use it to record, you will need to unplug the microphone to listen to the recording. Again, this is true about all smartphones.

This Y-Splitter allows you to plug in a microphone and a headphone to your mobile phone at the same time, with the microphone serving as the audio input channel and the headphone serving as the audio output channel.